#include<stdio.h>
#include<string.h>

int main()
{
	char a[1000]="Hello world";
	char b[1000]=" happy";
	char s[1000]={0};
	printf("%d  %d\n",strlen(a),strlen(b));
	strcat(a,b);
	puts(a);
	strcpy(s,a);
	puts(s);
	
}